A first example of a known conventional IC socket, is disclosed in Japanese Unexamined Patent Publication No. 6(1994)-151025 (FIG. 1, FIG. 3). This IC socket comprises a housing that holds a large number of contacts and has an IC package positioning base and a rotatable cover plate for pressing an IC package against the positioning base.
A second example of a known IC socket, is disclosed in Japanese Unexamined Patent Publication No. 5(1993)-174924 (FIG. 1, FIG. 3). This IC socket comprises a housing that holds a large number of contacts and has a PGA (Pin Grid Array) type IC package positioning base.
In the first known IC socket, the top of the positioning base is open. Therefore, there is a possibility that a corner of an IC package will strike the contacts of the IC socket, causing them to buckle or become deformed, if the IC package is dropped during mounting onto the IC socket or the like. In addition, there is a possibility that the IC package will not be accurately placed in a predetermined position, and will be mounted in an inclined manner.
In the second known IC socket, the IC package is of the PGA type. Therefore, the contacts of the IC socket are not exposed at an IC package mounting surface thereof. Accordingly, there is no possibility that the contacts will buckle or become deformed by a corner of the IC package, even if the IC package is dropped. However, in the case that the IC package is mounted in an inclined manner, it is difficult to correct the incorrect mounting state thereof. In the case that connections are established while the IC package is mounted in an inclined manner, there is a possibility that pins of the IC package will become deformed.